Modern system on chip (SoC) integrated circuits (ICs) (“SoC's”) can have multiple voltage domains to operate different parts at different supply voltages. The use of multiple voltage domains can allow for efficient power management. To transmit signals across voltage domains, a “level-shifter circuit” can be provided at the receiver to shift the supply voltage of the transmitted signal to the voltage domain of the receiver. Conventional level-shifter circuits require supply voltages from both voltage domains in order to shift supply voltage of a signal from one domain to another. These “multi-supply” level shifter circuits can cause power routing congestion in the SoC due to the need to provide multiple supply voltages at each receiver of signals transitioning between voltage domains. Further, in dynamically scalable SoCs, supply voltages can be unknown prior to silicon implementation.
A single-supply level-shifter circuit is another type of level-shifter that operates using a single supply in the voltage domain of the receiver. Existing single-supply level-shifter circuits have limited operating range, are slow over the range of operation, are unidirectional, and/or are implementation area intensive.